So you want to put a post-87 D-series in a 1G/3G?
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Original thread here: http://www.redpepperracing.com/forums/index.php?showtopic=20384
I have recently seen more and more questions about putting a 88+ model D-series into a 1G/3G. So I decided to share how I did mine. Please remember that this should only be used as a guide. These are the things that I have done. You may or may not agree with my methods, it is your choice to do as I did or use this to figure out a better way for yourself. Also I am a very bad speller so if I misspell anything forgive me.
This post is going to cover how I put a D15B7 into my 84 CRX. All other D-series engines will be similar.
First lets look as some of the things we will need and things that will need to be done.
1. Fuel Tank. Convert from carb to fuel injection. To do this we will need a fuel tank from an SI as well as the main fuel line from an SI and its fuel pump.
2. Axles. The 1G axles will not fit properly in the D tranny, and the D axles will not fit in the 1G hubs. You will need the D axles and the outer cv joints of the 1G.
3. Mounts. There is no after-market kit for putting d-series engines in a 1G(The EDM-AS model CRX has mounts for the D-series), so you are going to have to make custom ones. You will need all the mount from the d-series and the 1G to mix and match.
4. Shift linkage and stabilizer bar. Get the ones for the d-series.
5. Clutch. The 1G has a cable clutch while the D-series is hydraulic. You will be making an adapter.
6. Wiring. Lots of wiring to do and lots of choices to make on how to do it. At a minimum you will need a MPFI engine harness and the correct ECU for your engine.
Okay so lets get started by cleaning out the engine bay. Get that old engine, tranny, radiator, all the electrical stuff, vacuum and fuel lines all out of the way. Go ahead and drop the fuel tank and remove the main line from the car (Keep the main line and the vent line for later use). If you want to replace any steering or suspension components now would be a good time, also do any brake work that may be needed.
1. Fuel. First lets mount the fuel pump, just in front of the drivers side wheel there should be some thread ed holes already there that is where the pump needs to go so bolt it up. With the pump on, lets get the tank up. It is difficult to put the lines on and the nozzle all while hold the tank up, but it will go, just keep at it. Make sure you get the straps nice and tight. Install the SI main line and attach it to the pump. Leave the end in the engine unhooked until after the engine is in. So skip to the next thing and come back to when the engine is in. Okay so your almost done the engine is in and everything is hooked all you need is fuel and wiring right. Unhook the filter from its mount, if not already done. Weld the mount onto the firewall, it fits real nice just below the return and vent lines. Put the filter in its mounts and attach the lines now you have fuel.
2. Axles. Take the d-series shafts and remove the outer cv joints. Put the outer CV joints from the 1G onto the d-series shafts. The new modified shafts will now fit in the tranny and fit in the wheel hubs.
3. Mounts. I found it was easiest to have the engine suspend on a chain and using jacks as need to position the engine. Lift the engine into the bay and lower it enough to fit the axles into the tranny and the wheels. Put the hub nuts onto the shafts tight enough to hold them in place.
Notice how the front engine mount is close to fitting into the original location. That's where its going to go. Cut a small piece of 1/4" metal and drill 2 hole that line up with the 1G mounts holes. Place the shim in between the block and the mount and bolt it down. Connect the rubber mount the the stock frame mount.
Don't tighten the bolts all the way, you will need the slack to position the other mounts.
Next lets do the top tranny mount. Position the engine so that the axles are straight and the engine is level, also check to make sure that the engine is not sitting too high or too low. Use one or more jacks to obtain the correct position. Once you are happy with the position bolt the mount onto the tranny. You can easily see where the new frame mount will need to be welded, so make your marks on the frame and remove the engine.
Weld in the custom frame mount, and lower the engine back in place. It may be necessary to remove the mount from the tranny so it can be put in place easier and the reconnect it once the engine is in. bolt up the mount and check the position of the engine still good? great.
Next is the rear Tranny mount and it can be a pain. Take the 1G mount that bolted to the cross-member off and cut through the rubber and remove the top section.
Get the tranny mount from the D-series and cut the end of a little and do a bit of grinding. Take the top front engine mount from the D-series and grind the metal spacer in between the mount until you can fit it inside of the rear mount. It is hard to get in but just keep hammering, and grinding on it till it fits. Once its in drill a hole in the rear mount so that a bolt can be inserted. Now take the lower part of the 1G mount that we cut and get under the car. See the 2 holes where it bolted to the cross member, on the rear side of the cross-member you should be able to see a hole in between the 2 original holes, put the mount on and slide it over to the passenger side until it lines up with that hole, now drill out the other side and the other hole. Bolt it to the cross-member.
With the engine in test fit the tranny mount you will probably need to do more grinding and a little hammering on the firewall to get it to fit without hitting the body but it will fit. Once it fits tighten all the other mounting bolts and see how much space is between the two mounts, fill this space with 1/4inch shims. When you have the number of shims you need weld them all together. Test fit the mount again and mark where the holes need to be to bolt the mount to the frame mount.
Now pull all the mounts on last time and fill them with 3M window weld or a similar product.
4. Shift links. This one is easy, just take the D-series linkage and stabilizer bar and bolt them to the shifter, they're too long. So cut them, and bolt each end of both bars up, and mark where they need to be welded at. When making your mark on the shifter, make sure the tranny is in neutral and have someone hold the shifter in a neutral position also.
5. Clutch. Fabricate an adapter similar to the one in the pics. There is a way to convert the 1G to use the Hydro but I don't know the specifics about what needs to be done.
6. Electrical. You will at least need a MPFI engine harness and the proper ECU for engine. I swapped the entire car harness which made most of the wiring easy, but then I to make room for new guage cluster and turn signal switch.
That's everything I can think of. I'm sure theres lots of small stuff I forget, but at least this may help you get some ideas going.
